Enhanced characteristics of an uncooled microbolometer using vanadium–tungsten oxide as a thermometric material

To produce a highly sensitive uncooled microbolometer, the development of a high-performance thermometric material is essential. In this work, amorphous vanadium–tungsten oxide was developed as a thermometric material at a low temperature of $300°C$⁠, and the microbolometer, coupled with the material, was designed and fabricated using surface micromachining technology. The vanadium–tungsten oxide showed good properties for application to the microbolometer, such as a high-temperature coefficient of resistance of over $−4.0%∕K$ and good compatibility with the surface micromachining and integrated circuit fabrication process due to its low fabrication temperature. As a result, the uncooled microbolometer could be fabricated with high detectivity over $1.0×109cmHz1∕2∕W$ at a bias current of $7.5μA$ and a chopper frequency of $10–20Hz$⁠.